let a, b and c represent the measurements of the angles: angle A, angle B and angle C correspondingly

since they are angles in triangle their sum is equal to 180 degrees:

a + b + c = 180

the size of angle B is 5 times the size of angle A:

b = 5a

the size of angle C is 11 degrees less then 4 times angle A:

c = 4a - 11

by solving the system of equations:

a + b + c = 180

b = 5a

c = 4a - 11

we find:

a = 19.1 degrees

b = 95.5 degrees

c = 65.4 degrees

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the angles of the triangle are: angle A is 19.1 degrees, angle B is 95.5 degrees, angle C is 65.4 degrees.